title: Genetic diversity in three endangered pitcher plant species (Sarracenia; Sarraceniaceae) is lower than widespread congeners.
abstract: OBJECTIVE
  Narrow-ranging, rare species often exhibit levels of genetic diversity lower than more common or widespread congeners. These taxa are at increased risk of extinction due to threats associated with natural as well as anthropogenic events. We assessed genetic variation in three federally endangered Sarracenia species. We discuss maintenance of genetic diversity and evolutionary implications of rarity. •
  
  
  METHODS
  We analyzed three noncoding chloroplast regions and nine microsatellite loci in populations spanning the geographic ranges of S. oreophila, S. alabamensis, and S. jonesii. The same microsatellite loci were used to examine a single field site of three more widespread species (S. alata, S. leucophylla, and S. rubra subsp. wherryi). •
  
  
  RESULTS
  All three endangered species have experienced reductions in population size and numbers. All show considerably less variation than more widespread members of the genus. Sarracenia alabamensis maintains the greatest microsatellite variation but has the fewest remaining populations and may be under the greatest threat. More widespread S. oreophila maintains surprising chloroplast diversity, yet exhibits little microsatellite diversity. Sarracenia jonesii lacks chloroplast diversity, yet maintains greater microsatellite diversity than S. oreophila. •
  
  
  CONCLUSIONS
  The three endangered species differ in levels and structure of diversity, yet not in predictable ways, emphasizing that unique demographic and ecological histories, rather than current distribution and population size, best explain present patterns of genetic variation. Maintenance of remaining genetic variation is important, but preventing further habitat loss and degradation is critical.
authors.affiliation: 334 Math & Natural Science Building, Department of Biology, Lincoln Memorial University, 6965 Cumberland Gap Parkway, Harrogate, Tennessee 37752 USA.
authors.forename: M Steven
authors.initials: MS
authors.lastname: Furches
authors.forename: Randall L
authors.initials: RL
authors.lastname: Small
authors.forename: Anna
authors.initials: A
authors.lastname: Furches
mesh_terms: D000407:Alabama; D018742:DNA, Chloroplast / Q000235:genetics; D021901:DNA, Intergenic / Q000235:genetics; D056727:Endangered Species; D056426:Genetic Loci / Q000235:genetics; D014644:Genetic Variation; D006239:Haplotypes / Q000235:genetics; D018895:Microsatellite Repeats / Q000235:genetics; D010802:Phylogeny; D052583:Sarraceniaceae / Q000235:genetics*; D013045:Species Specificity
chemical_list: D018742:DNA, Chloroplast; D021901:DNA, Intergenic
keywords: 3′rps16-5′trnK; Sarracenia; Sarraceniaceae; atpI-atpH; endangered; endemic; microsatellites; noncoding chloroplast; trnS-trnG